1909] Bartlett, — Submarine Bog at Woods Hole 227 
that the plants of sea beaches are not generally halophytes, in the same 
sense that the plants of inland saline situations are, but are for the 
most part merely such plants of normally non-saline habitats as are 
able to withstand a high salt concentration without injury. These 
conclusions, considered in conjunction with the fact that a large pro- 
portion of the species of the beach and transition zone floras, although 
not necessarily always found within the limits of tide water, are, 
nevertheless, seldom found more than a few miles from the ocean, 
suggest that we may have to alter somewhat our conception of what 
constitutes a halophyte. The broad geographic ranges of the plants 
of these two transition zones (in part the same species as those which 
occur at the head of tide water in the region of the Bay of Fundy !) 
‘an not be correlated with their adaptability to growth in highly saline 
situations. If, however, we consider not absolute salinity but the 
ratio of saline constituents in the soil water, irrespective of absolute 
concentration, the possibility of correlating geographic range with 
physiological requirements becomes much greater. А  moment's 
inspection of an analysis of an average soil water (in which the concen- 
tration of mineral salts is very slight), will show how comparatively 
small an admixture of sea water would suffice to bring the ratio of 
elements into approximate agreement with sea water. Further 
addition of sea water would increase absolute salinity, but would 
change ratios very slightly. May it not be a useful working hypothesis 
that sea water, in whatever dilution, is physiologically normal with 
regard to the plants of salt marshes and sea beaches, and that their 
usual local distribution is due altogether to the operation of factors 
other than chemical? ‘The writer hopes to carry out some experi- 
mental work along the line of this suggestion. ‘The constitution of 
soll water is influenced many miles inland by salt spray from the ocean. 
“The normal chlorine, or maximum proportion of chlorine (present 
as common salt or sodium chloride) which may exist in ап uncon- 
taminated water, usually varies inversely as the distance from the sea, 
the range for Massachusetts being from 2.42 parts per 100,000 at 
Provincetown....to 0.06 parts in Berkshire County. ‘The normal 
chlorine not only depends upon proximity to the coast, but it is high- 
est on the salient and most exposed parts of the coast, where the surf 
breaks heavily and the salt spray is wafted inland most freely." ? 
1Ganong. The Vegetation of the Bay of Fundy Salt and Dyked Marshes; an Eco- 
logical Study. Bot. Gaz. xxxvi (1903), pp. 161, 280, 349, and 429. 
2 W. O. Crosby. U.S. Geol. Surv, Water Supply and Irrigation paper No. 114 (1905) 
Deka. 
